x86: GRUB Based Booting

Starting with the Solaris 10
1/06 release, the open source GNU GRand Unified Boot Loader
(GRUB) has been adopted in the Solaris OS for x86 based systems. GRUB is responsible
for loading a boot archive into the system's memory. A boot archive is a
collection of critical files that is needed during system startup before the
root (/) file system is mounted. The boot archive is
used to boot the Solaris OS.

The most notable change is the replacement of the Solaris Device Configuration Assistant with
the GRUB menu. The GRUB menu facilitates booting the different operating systems
that are installed on your system. The GRUB menu is displayed when you boot
an x86 based system. From the GRUB menu, you can select an OS instance to
install by using the arrow keys. If you do not make a selection, the default
OS instance is booted.

The GRUB based boot feature provides the following improvements:

Faster boot times

Installation from USB CD or DVD drives

Ability to boot from USB storage devices

Simplified DHCP setup for PXE boot (no vendor-specific options)

Elimination of all realmode drivers

Ability to use Solaris Live Upgrade and the GRUB menu to quickly
activate and fall back to boot environments